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Dendrites are important microstructures in single-crystal superalloys. The distribution of dendrites is closely related to the heat treatment process and mechanical properties of single-crystal superalloys. The primary dendrite arm spacing (PDAS) is an important length scale to describe the distribution of dendrites. In this work, the second-generation single crystal superalloy HT901 with a diameter of 15 mm was imaged under a metallurgical microscope. An automatic dendrite core identification and full-field quantitative statistical analysis method is proposed to automatically detect the dendrite core and calculate the local PDAS. The Faster R-CNN algorithm combined with test time augmentation (TTA) technology is used to automatically identify the dendrite cores. The local multi-directional algorithm combined with Voronoi tessellation is used to determine the local nearest neighbor dendrite and calculate the local PDAS and coordination number. The accuracy of using Faster R-CNN combined with TTA to detect the dendrite core of HT901 reaches 98.4%, which is 15.9% higher than using Faster R-CNN alone. The algorithm calculates the local PDAS of all dendrites in H901 and captures the Gaussian distribution of the local PDAS. The average PDAS determined by the Gaussian distribution is 415 μm, which is only a small difference from the average spacing λ¯ (420 μm) calculated by the traditional method. The technology analyzes the relationship between the local PDAS and the distance from the center of the sample. The local PDAS near the center of HT901 are larger than those near the edge. The results suggests that the method enables the rapid, accurate and quantitative dendritic distribution characterization.

Hainantoxin-IV (HNTX-IV) was isolated from the Chinese bird spider Ornithoctorcs hainana and identified as a novel antagonist of tetrodotoxin-sensitive (TTX-S) sodium channels. As revealed by the solution structure of HNTX-IV solved by two-dimensional nuclear magnetic resonance (2D-NMR), HNTX-IV adopts an inhibitor cystine knot motif. To check the role of basic residues during HNTX-IV’s interaction with TTX-S sodium channels, R26A and K27A mutants of HNTX-IV were constructed by solid-phase chemical synthesis. The synthesized peptides were purified and refolded under optimized oxidation conditions. Correct synthesis and folding were confirmed by MALDI-TOF mass spectrometry and NMR spectroscopy, respectively. Using the whole-cell patch-clamp technique, Lys27 but not Arg26 was identified as a key residue for HNTX-IV’s bioactivity against TTX-S sodium channels, because R26A-HNTX-IV showed slightly reduced activity and K27A-HNTX-IV showed almost no inhibition.

A method for the determination of trace amounts of niobium in steel samples by reversed-phase high-performance liquid chromatography (RP-HPLC) was developed. The iron matrix was removed from sample solution by using methyl isobutyl ketone as an extraction agent. 2-(5-Bromo-2-pyridylazo)-5-diethylamino phenol (5-Br-PADAP) was used as a pre-column chelating agent to form ternary complex with Nb(V) and tartaric acid. The Nb(V) complex was eluted within 3 min with a mobile phase of methanol–water (56:44 (v/v)) containing 10 mmol/l acetate buffer (pH 3.5) on a C 18 column and determined with spectrophotometric detection at 600 nm. The detection limit of this method for Nb in iron or/and steel sample was 0.015 μg/g. The proposed method was applied to the analysis of trace amounts of niobium in cast iron.

This paper introduces the design scheme of transducer of complex electrical parameters with control unit based on DSP. The general hardware is introduced, principles of control are described and the hardware and software are described in detail. The PC is communicated with transducer by RS-485. The measuring results are presented at last, It was shown that the system has advantages in simple structure, high reliability and high quality. It has a practical value and wide application prospects.

The paper introduces the design of transducer of complex electrical parameters based on TMS320F2812. The general hardware is introduced, principles of control are described and the hardware is described in detail. Meanwhile, the program realizes all the transducer of complex electrical parameters functions and the software is programmed with C and assembler language, which ensures that the software has clear structure and the short development cycle, at the same time, the high efficiency can be obtained. The experiment result shows that the transducer of complex electrical parameters has perfect regulating control function and practical value.

A method for the simultaneous determination of Nb and Ta in steel and alloy by reversed-phase high-performance liquid chromatography (RP-HPLC) was proposed. 2-(5-Bromo-2-pyridylazo)-5-diethylamino phenol (5-Br-PADAP) was used as a pre-column chelating agent to form a ternary complex with Nb(V) and Ta(V) and tartaric acid. The ternary complexes of Nb(V) and Ta(V) were eluted within 8 min on a C 18 column with a mobile phase of methanol–water (55:45, v/v) containing 10 mmol l −1 acetate buffer (pH3.5) and determined with spectrophotometric detection at 598 nm. The detection limits for Nb(V) and Ta(V) were 0.60 and 0.72 μg l −1 , respectively, when the ratio of signal-to-noise is 3. The proposed method was used to analyze Nb and Ta in cast iron, alloy and stainless steel.

The fabrication and measurement results of the vibration energy harvester arrays based on the piezoelectric aluminum nitride (AlN) film are presented. The structure design and fabrication process of the device are introduced. The key material, the AlN film with crystal orientation (002), was deposited by pulsed-DC magnetron sputtering and characterized by X-ray diffraction (XRD). The resonant frequency, power out, and the open circuit voltage of the device are detected. The optimized load of 80 kΩ and a remarkable maximum power out of 30.4 μW are obtained when the acceleration of 0.9g (g is standard gravity acceleration) is applied.

A novel micro-opto-electro-mechanical system (MOEMS) accelerometer based on Raman—Nath diffraction is presented. It mainly consists of an FPW delay line oscillator and optical strip waveguides. The fundamental theories and principles of the device are introduced briefly. A flexural plate-wave delay-line oscillator is designed to work as an acousto-optic (AO) shifter, which has a Klein—Cook parameter of 0.38. Single-mode optical strip waveguides of 2 μm in width and thicknesses of 0.6 μm are designed by using the effective index method for light transmission. The Ey00 mode waveguide polarizers are designed to ensure the consistency of the light polarization in the waveguides. The fabrication process, based on (100) oriented, 450-μm-thick silicon wafers is proposed in detail, and some difficulties in the process are discussed carefully. At last, a series of process tests are undertaken to solve the proposed problems. The results indicate that the proposed design and fabrication process of the device is dependable and realizable.

This work describes the Nanji Islands marine natural reserves information system. The system is developed specially for Nanji Islands using remote sensing, geographical information system, database, and computer techniques. In Nanji Islands marine natural reserves information system, spatial database, remote sensing information database, shellfish and alga database and so on are established, and the system have the functions managing, updating and querying.